The world is experiencing a wave of displacement by violent conflict not seen since World War II. The United Nations estimated that 59.5 million people were displaced at the start of the year, most of them in poorer countries.

Most are within their countries of origin. But millions have also been driven beyond their national borders, living in camps and desperate to find asylum for themselves and their children.

After World War II, there were still a number of prosperous places with open immigration policies, especially for Europeans: Australia, the US, and Argentina, to name a few took on hundreds of thousands of people. But the 21st century has brought far tighter borders, and strong anti-immigrant sentiment in former migrant havens. It doesn't help that today's refugees are far darker-skinned than in 1945.

The numbers approach the limit of human understanding. The UN today estimates that 3 million Iraqis have been displaced from their homes; in Syria, the numbers of the internally displaced and refugees in Jordan, Turkey, and Lebanon exceed 12 million.

About 230,000 Muslim Rohingya of Myanmar, targeted in a series of pogroms in recent years by the country's Buddhist majority, are now internally displaced and living in squalid camps. There are a quarter of a million people displaced from other ethnic groups around the country. In Africa, both conflict and lack of economic opportunity have led tens of thousands from Nigeria, Senegal, and elsewhere to transit dangerous countries in North Africa like Libya to get onto rickety smuggling boats headed across the Mediterranean.

In the old days, of course, it wasn't exactly a pretty picture. Australia, for instance, was transformed by postwar migration. Between 1945 and 1965, 2 million migrants arrived in Australia, increasing its population by 25 percent. But the country was highly discriminatory. The country maintained what was called the "White Australia" policy until 1972.

Now, however, Australia is in some ways a pilot project for dealing with the latest wave of migrants. Its model relies on shoveling would-be asylum seekers into out-of-sight, out-of-mind offshore internment camps where evidence of human rights abuses and squalor are mounting. The policy is popular at home, and appears to have been effective in keeping new arrivals off its shores. Prime Minister Tony Abbott has touted the Australian model to other countries, saying it's the only solution to a model problem.

Australia's model

The centerpiece of Australia's effort is internment camps set up on the tiny, impoverished island nation of Nauru and on Manus, an island off the coast of impoverished, but not so tiny, Papua New Guinea. The current policy dates back to 2001, when the conservative John Howard was prime minister.

When Kevin Rudd was elected prime minister and ushered in a labor government in 2007, the policy was scotched. Incoming Immigration Minister Chris Evans called it "a cynical, costly and ultimately unsuccessful exercise," and said it had cost the government about $223 million. But it got results. Asylum seeker arrivals – Afghans, Iraqis, Vietnamese, and Rohingyas, mostly – dwindled to almost nothing. A measure of the popularity of the measure was that while Mr. Rudd had campaigned on changing the policy, Labour's Julia Gillard revived the practice when she replacedRudd in 2010.

Since Mr. Abbott won the premiership in 2013, the screws have been tightened. Australia is now spending about $1 billion a year on the detention centers, which are also placed at the Australian territory of Christmas Island, near Indonesia, and on the mainland. Much of the money has gone to the host governments and to private Australian contractors.

Since 2013, all people arriving in Australian waters by boat have been sent to Nauru and Manus, and there is little hope of successful resettlement. In 2013, 300 or so boats reached Australia. In 2014, the total was 1.

"Asylum claims are not processed in a fair, transparent or expedient manner, at a significant cost to detainees’ physical and mental health. There are reports of physical and sexual abuse of detainees. Recent hunger strikes on Manus Island point to the poor conditions endured by asylum seekers and the uncertainty they face because of prolonged refugee status determination procedures," Human Rights Watch wrote earlier this year. "The centers are closed and UN experts, journalists, and human rights organizations have all experienced difficulties in obtaining access to independently assess conditions. All media and staff working in offshore processing centers are required to sign Deeds of Confidentiality with the Department of Immigration."

News of horrific conditions at the camps continues to leak out, despite the best efforts of the Pacific nations involved and their partner, Australia, at squashing the flow of information. Many Internet services, including Facebook, were severely restricted on Nauru earlier this year, and detainees face up to seven years in jail for protesting their conditions.

In May, Australia passed a law that could bring jail time to contractors who have worked on Nauru if they speak out about what they saw. "It's all very vague it's all very secretive, it's frightening I think," David Issacs, an Australian pediatrician who worked on Nauru and came home with tales of desperate children harming themselves (one boy sewed his mouth shut) and sexual assaults by guards, told the Australian Broadcasting Corp. "Now it says that if I see a child that's in danger or that's seriously ill because of the conditions there and their mental health is really bad, even if I come back to Australia and talk about it in to the media, even put it on Facebook, I could face two years in prison."

In January, a riot broke out among 1,000 men detained on Manus, after water supplies were disrupted for weeks. But while human rights black eyes pile up, the policy is popular. When allegations emerged earlier this month that the Abbott government has been paying off Indonesian people smugglers to take their cargo elsewhere (which the government has not denied) this is how Mr. Abbott responded:

"There’s really only one thing to say here ... and that is that we have stopped the boats. That’s good for Australia, it’s good for Indonesia and it’s particularly good for all of those who want to see a better world, because if the boats start again, the deaths start again.”

In the case of Europe, about 170,000 migrants took boats from Libya to Italy last year, and so far this year, the total is above 57,000. Abbott has urged Europe to follow suit, and many are listening. Turning back boats can work for a while, perhaps. But the pressures forcing people to take desperate measures are only building.